Dispensing Means for a Liquid

ABSTRACT

A dispensing means for delivering a dose of a first liquid into a second liquid is provided, the dispensing means comprising an enclosure ( 2, 3, 4 ) for accommodating the first liquid ( 12, 13 ), and dispersion means ( 15, 16 ), the dispersion means being adapted to receive a dose of the first liquid from the enclosure, and to deliver a dose of the first liquid into the second liquid when subjected to a flow of the second liquid. The dispersion means comprises a structure ( 15, 16 ) along which the first liquid is transportable and, in use, substantially all of the surface area of the dispersion means is exposed to the atmosphere. A surface of the dispersion means is curved such that the flow of the liquid when incident upon the surface is drawn over at least a portion of the surface.

FIELD OF THE INVENTION

This invention relates to dispensing means for a liquid, in particular to dispensing means for delivering a dose of a liquid product into a lavatory bowl.

BACKGROUND TO THE INVENTION

Toilet bowls require care to prevent the buildup of unsightly deposits, to reduce malodour and prevent the growth of bacteria. There are in existence many forms of toilet bowl cleaning products. One type of product comprises a solid block of cleansing and freshening agents that is suspended from the rim of a toilet bowl in a container placed in the path of the flushing water. U.S. Pat. No. 3,529,309 shows an example of this type of toilet bowl cleaning product. Unfortunately, solid cleaning blocks have a short lifetime and the release of cleansing and freshening agents varies as the block deteriorates.

Toilet cleaning systems that use liquid cleaning agents have also been developed. For example, European Patent Application EP-0538957 discloses a cleansing and/or freshening unit capable of being suspended from the rim of a toilet bowl for the purpose of introducing liquid active substances from a bottle into flushing water. Unfortunately, one problem with liquid dispensing devices such as disclosed in EP-0538957 is that as the liquid level in the dispensing bottle falls, the rate at which liquid is dispensed also falls.

European Patent Application EP-0785315 describes a dispenser that attempts to overcome the problem associated with devices such as described in EP-0538957. This dispenser includes a dispensing bottle that allows liquid to flow from it while permitting air from outside the bottle to flow into it. Unfortunately, the device described in EP-0785315 requires the use of a porous, liquid-absorbing mass that is in continuous contact with the cleaning liquid contained in the dispensing bottle. Apart from being expensive to manufacture, this dispensing device is unable to provide precise control over the volume of liquids dispensed in the flushing water.

In addition to problems associated with rate of delivery of liquid active substances, they also have problems associated with the difficulty of incorporating certain actives, such as bleaches and various hypochlorites, as these materials may affect properties of the components of the liquid active substance. For example, bleaches and hypochlorites will typically fade the color of a dye and destroy a fragrance upon extended contact. Also, certain incompatible cleaning actives may not be stable when mixed and through the resulting chemical interaction, the efficacy of the individual cleaning actives may be decreased. In particular, the inability to incorporate bleaches and hypochlorites into a liquid active substance is especially detrimental as bleaches and hypochlorites are particularly effective in destroying bacteria and preventing biofilm formation.

These limitations in liquid dispensing cleaning systems have prevented their optimization.

There is a need for an improved device that can dispense precisely controlled quantities of cleaning and freshening liquids from under the rim of a toilet bowl, and that can deliver a greater variety of cleaning actives to a toilet bowl, including incompatible liquid active compositions.

SUMMARY OF THE INVENTION

According to a first aspect of the invention there is provided dispensing means for delivering a dose of a first liquid into a second liquid, the dispensing means comprising an enclosure for accommodating the first liquid, and dispersion means, the dispersion means being adapted to receive a dose of the first liquid from the enclosure, and to deliver a dose of the first liquid into the second liquid when subjected to a flow of the second liquid, wherein the dispersion means comprises a structure along which the first liquid is transportable and, in use, substantially all of the surface area of the dispersion means is exposed to the atmosphere.

The invention therefore provides dispensing means that, for a given volume of the dispensing means, has a greater surface area from which evaporation of the first liquid can take place than known dispensing means.

Preferably the dispensing means is adapted to dispense a plurality of individual doses of a first liquid product in succession, one dose being delivered each time the dispersion means is subjected to a flow of the second liquid.

In a preferred embodiment of the invention the dispensing means is for suspension below a rim of a lavatory bowl, the first liquid product then being a suitable additive to the water (forming the second liquid) being flushed into the lavatory bowl. Suitable additives include fragrances, surfactants, bleaches, dyes, disinfectants, insecticides, deodorants and cleaning agents.

Where the first liquid product includes a fragrance, the invention provides a dispensing means, which, when suspended below a rim of a lavatory bowl, enables the fragrance to be released from the dispensing means between flushes of the lavatory more effectively than by known dispensing means.

The invention therefore further provides a dispensing means that can deliver cleaning and/or freshening lavatory bowl treatment preparations from under the rim of a toilet bowl before, during and after flushing of the lavatory.

The structure along which the first liquid is transportable may advantageously be provided with at least one internal channel, which, in use, is exposed to the atmosphere so as to increase the surface area of the structure available for evaporation of the first liquid.

The structure may be provided in a range of shapes, e.g. a cube, plate, ring, oval, sphere, rod, or any decorative shape or mixture of shapes.

In the preferred embodiment of the invention, however, the structure is a tube and, in use, an internal surface of the tube is exposed to the atmosphere.

The structure may advantageously be formed with at least one capillary channel for transporting the first liquid along the structure by capillary action.

Alternatively, or in addition, the structure may advantageously be formed from a porous material, preferably a porous non-water-soluble plastics material, capable of transporting the first liquid along the structure by capillary action. Suitable non-water-soluble plastics materials include polypropylene and polyethylene.

In use at least 65% of the surface area of the dispersion means may advantageously be exposed to the atmosphere, and preferably at least 75% of the surface area. In preferred embodiments of the invention, in use, at least 85% of the surface area of the dispersion means is exposed to the atmosphere.

According to a second aspect of the invention there is provided dispensing means for delivering a dose of a liquid product into a liquid, the dispensing means comprising an enclosure for accommodating the liquid product, and dispersion means adapted to receive a dose of the liquid product from the enclosure, and to deliver a dose of the liquid product into the liquid when subjected to a flow of the liquid, wherein a surface of the dispersion means is curved such that the flow of the liquid, when incident upon the surface, is drawn over at least a portion of the surface.

The term “liquid product” is intended to encompass solutions, suspensions and gels.

The invention therefore further provides dispensing means that can dispense a larger dose of a given liquid product into a given flow of liquid than known dispensing means, because the flow of liquid not only comes into contact with that part of the dispersion means on which it is incident, but also comes into contact with at least a portion of the dispersion means over which it is drawn.

The dispersion means is preferably elongate and may, for example, be oval in cross-section, or be shaped like an aerofoil. Preferably, however, the dispersion means is cylindrical.

The preferred embodiment of the invention is a liquid rim dispenser adapted to be suspended below a rim of a lavatory bowl, the dispersion means being subjected to a flow of water upon flushing the lavatory.

Where the dispersion means is elongate, the dispersion means is preferably arranged such that when the dispensing means is suspended below a rim of a lavatory bowl, the dispersion means is substantially vertical, i.e. substantially perpendicular to the flow of water.

Preferably the enclosure is divided into two separate enclosures, each with a respective dispersion means, and the surface of at least one of the dispersion means is curved such that when the dispersion means is subjected to the flow of water, the water incident on the surface is drawn over at least a portion of the surface and directed onto a surface of the other dispersion means.

The arrangement whereby the enclosure is divided into two separate enclosures allows the dispensing means to deliver a greater variety of liquid products into the lavatory bowl than known dispensing means. In particular, this arrangement allows the dispensing means to deliver two different liquid products into the lavatory bowl and is useful where it is undesirable for the two liquid products to be mixed before they are delivered into the lavatory bowl, for example where one liquid product is a bleach solution and the other is a fragrance, since the fragrance would be broken down by the bleach solution, and the bleach solution would be neutralised in breaking down the fragrance.

In this way most (or all) of the undesirable chemical interaction between the two liquid products is preempted and a user of the dispensing means will benefit from the superior properties of each of the incompatible liquid products through a single delivery of each of the liquid products.

Moreover, the arrangement whereby flush water incident upon one of the dispersion means is directed onto the other dispersion means results in relatively even delivery of the liquid product from the two enclosures, rather than greater delivery of the liquid product from the enclosure the dispersion means of which is upstream in the flow of flush water, provided that the dispensing means is suspended in the lavatory bowl with the correct dispersion means upstream in the flow of flush water.

In the preferred embodiment the surfaces of both the dispersion means are curved such that when either dispersion means is subjected to the flow of water, the water incident on the surface of the dispersion means is drawn over at least a portion of the surface and directed onto a surface of the other dispersion means.

With this arrangement it is immaterial which dispersion means is upstream in the flow of the flush water, making the dispensing means simple to install in the lavatory bowl.

Preferably the liquid product comprises at least one fragrance ingredient having a ClogP of 3 or more and a boiling point of 250° C. or lower. This has been found to be particularly effective at providing an odour counteracting and freshening effect when used with the liquid rim dispenser of this invention.

By way of explanation, the logP of many fragrance ingredients have been reported. For example, the Pomona92 database (available from Daylight Chemical Information Systems, Inc. (Daylight CIS), Irvine, Calif.) contains many logP values, along with citations to the original literature. However, the logP values are most conveniently calculated by the “CLOGP” program, also available from Daylight CIS. This program lists experimental logP values when they are available in the Pomona92 database. The “calculated logP” (ClogP) is determined by the fragment approach of Hansch and Leo (cf., A. Leo, in Comprehensive Medicinal Chemistry, Vol. 4, C. Hansch, P. G. Sammens, J. B. Taylor and C. A. Ramsden, Eds., p. 295, Pergamon Press, 1990, incorporated herein by reference). The fragment approach is based on the chemical structure of each fragrance ingredient, and takes into account the numbers and types of atoms, the atom connectivity, and chemical bonding. The ClogP values, which are the most reliable and widely used estimates for this physicochemical property, are used instead of the experimental logP values in the selection of fragrance ingredients which are useful in the present invention.

In the fragrance composition art, some materials having no odour or very faint odour are used in addition to fragrance ingredients proper (those fragrance ingredients that give the fragrance composition its fragrance) as diluents or extenders to form a fragrance composition. Non-limiting examples of these materials are dipropylene glycol, diethyl phthalate, triethyl citrate, isopropyl myristate, and benzyl benzoate. These materials are used, for example, for diluting and stabilising the fragrance ingredients in fragrance compositions. For the purposes of this specification, these materials are not counted in the weight percentages of fragrance ingredients in fragrance compositions.

Where the liquid product includes a fragrance composition, the fragrance composition preferably comprises at least 30% by weight of at least one fragrance ingredient having a ClogP of 3 or more and a boiling point of 250° C. or lower; even more preferably at least 40% by weight; and more preferably still at least 50% by weight.

According to a third aspect of the invention there is provided a liquid rim dispenser intended for suspension from a rim of a toilet bowl adjacent a wall thereof, in the path of flushing water during a flushing operation, said liquid rim dispenser comprising a container for holding at least one liquid active composition, a base for holding the container, at least one hollow porous substrate supported by the base and means for suspending the base from the rim of a toilet bowl, and wherein the internal surface of the hollow porous substrate is open to the surrounding atmosphere.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described, by way of example, with reference to the attached drawing figures, in which:

FIG. 1 is a front view of an enclosure of dispensing means in accordance with the invention;

FIG. 2 is a partial cross-sectional front view of dispersion means of dispensing means in accordance with the invention;

FIG. 3 is a partial cross-sectional front view of the enclosure of FIG. 1 and dispersion means of FIG. 2 assembled to form dispensing means in accordance with the invention;

FIG. 4 is a top plan view of the dispersion means of FIGS. 2 and 3;

FIG. 5 is a front view of the dispersion means of FIGS. 2 to 4;

FIG. 6 is a bottom plan view of the dispersion means of FIGS. 2 to 5, showing the dispersion means being subjected to a flow of liquid; and

FIG. 7 is a graph of decrease in mass of a dispensing means in accordance with the invention against number of times the display means is subjected to a flow of liquid.

DETAILED DESCRIPTION OF AN EMBODIMENT

The enclosure of FIG. 1 is in the form of a container 2 that has two compartments 3 and 4 divided by a partition 5 separating liquid active compositions 12 and 13. Two outlets 6 and 7 are fitted with sealing components 8 and 9. Each sealing component 8 and 9 has a respective outlet tube 10 and 11.

The container 2 may be made from any suitable material, such as a plastics material (for instance polyethylene). Preferably the container 2 is made from a transparent material to allow the level of liquid active compositions to be viewed. The container 2 may be manufactured by any suitable method, and may be a complete moulding or separate units that may be joined together by any suitable means such as by adhesive.

The liquid active compositions 12 and 13 may be the same or different compositions. Additionally, they may be the same colour or they may be differently coloured to differentiate them from each other.

The dispersion means of FIG. 2 is in the form of a holder 14, to which two hollow porous cylindrical substrates 15 and 16 are attached as shown. The holder 14 provides a receptacle for receiving and supporting the container 2, and may be manufactured by any suitable method, such as by injection moulding. The holder 14 has a strap 23 for suspending the holder 14 from a rim of a toilet bowl.

The holder 14 allows for the two cylindrical substrates 15 and 16 to be alongside one another in a symmetrical arrangement. The bottom surface 19 of the holder 14 has two annular receptacles 26A and 26B formed by two outer cylindrical walls 17 and two inner cylindrical walls 18 arranged concentrically. The annular receptacles 26A and 26B receive the hollow porous cylindrical substrates 15 and 16.

Upstanding from the bottom surface 19 of the holder 14 are two piercing elements 20. A vertical cylindrical wall 21 surrounds each piercing element 20. The inside wall of each vertical cylindrical wall 21 has a series of vertical grooves 22 that function as air ducts.

Turning to FIG. 3, this shows container 2 fitted into the holder 14 to make dispensing means in the form of a liquid rim dispenser intended for suspension from a rim of a lavatory bowl adjacent a wall thereof, in the path of flushing water during a flushing operation.

The piercing element 20 of the holder 14 has entered and broken the interior of sealing component 8 to allow a portion of liquid active composition 12 to flow out of outlet tube 10. The portion of the liquid active composition 12 is contained within the vertical cylindrical wall 21. The height of the bottom of the outlet tube 10 relative to bottom surface 19 limits the portion of liquid active composition 12 contained within vertical cylindrical wall 21 to a shallow depth of a few millimetres and this level is maintained automatically in a manner not unlike that of a “chicken feeder”. The air ducts provided by the vertical grooves 22 maintain atmospheric pressure above the liquid within the vertical cylindrical wall 21.

Turning to FIG. 4, a series of slots 24 are spaced equidistantly and adjacent to the inside surface of the vertical cylindrical wall 21. Radial channels 25 formed into the upper surface of bottom surface 19 radiate outwards from piercing element 20. The radial channels 25 provide a conduit to slots 24 and allow liquid active compositions 12 and 13 to pass through bottom surface 19. The slots 24 are aligned to communicate the liquid active compositions 12 and 13 between the two concentrically arranged cylindrical walls 17 and 18 of the two annular receptacles 26A and 26B that support the hollow porous cylindrical substrates 15 and 16. It is essential that there are no gaps between the hollow porous cylindrical substrates 15 and 16 and the two annular receptacles 26A and 26B supporting them as this could lead to liquid active compositions 12 and 13 becoming liberated on the outer and/or inner surface of the hollow porous cylindrical substrates 15 and 16 resulting in uncontrolled release of the liquid active compositions 12 and 13. If required, the hollow porous cylindrical substrates 15 and 16 may be fixed to annular receptacles 26A and 26B through the use of any suitable adhesive, but care must be taken not to block the pores of the hollow porous cylindrical substrates 15 and 16.

FIG. 5 simply corresponds to FIG. 2 without the cut away portion.

The hollow porous cylindrical substrates 15 and 16 become loaded with liquid active compositions 12 and 13 from the top downwards because liquid active compositions 12 and 13 pass down through slots 24 and into the top of the hollow porous cylindrical substrates 15 and 16. Capillary action plus gravity act to exert a downward pull on the liquid active compositions 12 and 13 so that the hollow porous cylindrical substrates 15 and 16 become charged quickly with liquid active compositions 12 and 13. Once the hollow porous cylindrical substrates 15 and 16 are loaded with liquid active compositions 12 and 13 they retain them against the force of gravity.

The liquid rim dispenser is intended to operate when mounted on the rim of a toilet bowl and flush water is washed over the hollow porous substrates 15 and 16. The liquid rim dispenser dispenses amounts of the liquid active compositions 12 and 13 onto the hollow porous substrates 15 and 16. The large surface area of the hollow porous substrates, in comparison with prior art dispensing devices, allows for increased evaporation of fragrance and thus improved continuous air freshening as both the external and internal surfaces of the substrates are exposed to the atmosphere. When the toilet is flushed, water is directed over the hollow porous substrate or substrates to mix liquid active compositions with flush water and deliver them to the toilet bowl. The mixing of flush water to any surfactant emanating from the substrate is extremely efficient in generating large amounts of foam.

After each flush, gravity pulls downwards any water deposited onto the hollow porous cylindrical substrates 15 and 16 while at the same time pulling liquid active compositions 12 and 13 through the hollow porous cylindrical substrates 15 and 16 to reload them.

It is believed that the liquid rim dispenser of the invention is better able than known liquid rim dispensers to prevent flush water from entering the dispenser to dilute the liquid active compositions in the container compartments 3 and 4.

The liquid rim dispenser therefore can convey the liquid active compositions from the container to the cylindrical substrates in a controlled and consistent manner, resulting in a controlled, consistent amount of the liquid active compositions being delivered into the lavatory bowl with each flush.

The ability of the curved surfaces of the hollow porous cylindrical substrates 15 and 16 to pull the tangential supply of flush water around these surfaces is due to the Coanda effect and allows whichever of the hollow porous cylindrical substrates 15 and 16 that is situated “upstream” to the flow of flush water to deflect it onto whichever of the hollow porous cylindrical substrates 15 and 16 that is situated downstream. This results in liquid active compositions 12 and 13 being liberated at approximately the same rate due to the flush water being distributed fairly evenly across both substrates. FIG. 6 shows the base of holder 14, with flush water F superimposed upon it. This illustrates how flush water F is deflected from whichever of the hollow porous cylindrical substrates 15 and 16 that is upstream to the flow of flush water F onto whichever of the hollow porous cylindrical substrates 15 and 16 that is downstream to the flow of flush water F.

FIG. 7 shows the decrease in mass of a dispensing means in the form of a liquid rim dispenser with a single compartment and a single porous cylinder when repeatedly subjected to flush water in a lavatory bowl. The straight-line characteristic of the graph illustrates the controlled and consistent manner of delivery of a liquid active composition by the liquid rim dispenser.

It will be appreciated by those skilled in the art that the liquid rim dispenser of the present invention can be readily adapted for use with a wide variety of liquid active compositions to meet different criteria in terms of colour, foam forming, odour release, cleaning, disinfection, desired number of flushing operations per dispenser, and other considerations.

The rheological behaviour of the active compositions 12 and 13 are selected with regard to the pore size of the porous substrates 15 and 16, to ensure there is no leakage and that the active compositions are drawn through the porous substrates to provide a sufficient dose of the active compositions. Optimum flow-rate of the active compositions through the porous substrates may be established by one skilled in the art through the use of, for example, d'Arcy's Law: The flow rate is reliant on the size and number of pores and fluid viscosity. To ensure that the liquid active compositions 12 and 13 are dispensed at the same rate the viscosities of the liquid active compositions should be similar, and should lie within the range of 50 to 4,000 centipoises at 25° C.

Examples of the more preferred fragrance ingredients for use in the liquid active compositions include the following:

ALDEHYDE C10 (DECANAL)* ALDEHYDE C11 (UNDECENAL) ALDEHYDE C9 (NONANAL) ALDEHYDE MNA ALLYL AMYL GLYCOLATE* ALLYL HEPTANOATE ALLYL HEXANOATE AMYL BUTYRATE AZARBRE (Q) BORNEOL CARVACROL CARYOPHYLLENE CISTULATE (Q) CITRAL CITRAL DIETHYL ACETAL CITRONELLAL CITRONELLOL CITRONELLYL ACETATE CITRONELLYL NITRILE PHENYLETHYL BUTYL ETHER CUMIN NITRILE CYCLOHEXYLETHYL ACETATE

CYMENE, para- DAMASCENONE, beta- DAMASCONE, alpha- DAMASCONE, beta- DAMASCONE, delta- 4-trans-DECENAL

DEC-9-ENOL DIHYDROJASMONE DIHYDROLINALOL DIHYDROMYRCENOL* DIHYDROMYRCENYL ACETATE DIHYDROTERPINEOL (MENTHANOL)* DIHYDROTERPINYL ACETATE* ETHYL HEPTANOATE ETHYL SAFRANATE FLORHYDRAL FRUTONILE (Q) GERANIOL GERANYL ACETATE* GERANYL NITRILE* HERBANATE INONYL ACETATE* ISOBORNYL ACETATE* ISOPENTYRATE JASMATONE (Q) LIMONENE LINALOL* LINALYL ACETATE* MACEAL (Q) MAYOL MENTHOL* MENTHYL ACETATE METHYL CHAVICOL METHYL OCTINE CARBONATE METHYL PAMPLEMOUSSE (G) MYRCENE NEO BERGAMATE FORTE NEOCASPIRENE NEROL NOPYL ACETATE OCTYL ACETATE ORTHOLATE (Q)* Para Tert Butyl Cyclohexanol PARA TERT BUTYL CYCLOHEXYL ACETATE* PELARGENE (Q) Phenethyl Isopropyl Ether PHENYLETHYL ISOBUTYRATE RHUBAFURAN (Q) ROSE OXIDE TERPINOLENE* TERPINYL ACETATE* TETRAHYDROGERANIOL TETRAHYDROLINALOL TETRAHYDROLINALYL ACETATE TETRAHYDROMYRCENOL TONALID UNDECAVERTOL VERTENEX YLANGENE

Of these the more preferred fragrance ingredients are:

ALDEHYDE C10 (DECANAL) Allyl Amyl Glycolate DIHYDROMYRCENOL DIHYDROTERPINEOL (MENTHANOL) DIHYDROTERPINYL ACETATE GERANYL ACETATE GERANYL NITRILE INONYL ACETATE ISOBORNYL ACETATE LINALOL LINALYL ACETATE MENTHOL ORTHOLATE (Q) Para Tert Butyl Cyclohexyl Acetate TERPINOLENE TERPINYL ACETATE

Materials are obtainable from the following suppliers: for those materials labeled “(Q)”—Quest International, and for those materials labeled “(G)”—Givaudan.

It will be apparent that the foregoing description relates only to one embodiment of the invention, and that the invention encompasses other embodiments as defined by the claims set out hereafter. In particular, it is to be understood that this invention also encompasses dispensing means that have less than or more than two dispersion means and the enclosures of which contain less than or more than two liquids or liquid products. 

1-22. (canceled)
 23. Dispensing means for delivering a dose of a first liquid into a second liquid, the dispensing means comprising an enclosure for accommodating the first liquid, and dispersion means, the dispersion means being adapted to receive a dose of the first liquid from the enclosure, and to deliver a dose of the first liquid into the second liquid when subjected to a flow of the second liquid, wherein the dispersion means comprise a structure along which the first liquid is transportable, the structure being a tube, characterised in that, in use, a wall of the tube is substantially vertical and both an internal and an external surface of the tube are exposed to the atmosphere, such that substantially all of the surface area of the dispersion means is exposed to the atmosphere.
 24. Dispensing means according to claim 23, wherein the dispensing means are for suspension below a rim of a lavatory bowl, the first liquid being a suitable additive to water (forming the second liquid) being flushed into the lavatory bowl.
 25. Dispensing means according to claim 23, wherein the structure is formed with at least one capillary channel for transporting the first liquid along the structure by capillary action.
 26. Dispensing means according to claim 23, wherein the structure is formed from a porous material capable of transporting the first liquid along the structure by capillary action.
 27. Dispensing means according to claim 23, wherein a surface of the dispersion means is curved such that the flow of the second liquid, when incident upon the surface, is drawn over at least a portion of the surface.
 28. Dispensing means according to claim 27, wherein the enclosure is divided into two separate enclosures, each with respective dispersion means, and the surface of at least one of the dispersion means is curved such that when the dispersion means are subjected to the flow of the second liquid, the second liquid incident on the surface is drawn over at least a portion of the surface and directed onto a surface of the other dispersion means.
 29. Dispensing means according to claim 28, wherein the surfaces of both the dispersion means are curved such that when either dispersion means are subjected to the flow of the second liquid, the second liquid incident on the surface of the dispersion means is drawn over at least a portion of the surface and directed onto a surface of the other dispersion means.
 30. A liquid rim dispenser intended for suspension from a rim of a toilet bowl adjacent a wall thereof, in the path of flushing water during a flushing operation, said liquid rim dispenser comprising a container for holding at least one liquid active composition, a base for holding the container, at least one cylindrical hollow porous substrate supported by the base and means for suspending the base from the rim of a toilet bowl, the internal surface of the hollow porous substrate being open to the surrounding atmosphere, characterised in that the hollow porous substrate is arranged such that, in use, the wall of the substrate is substantially vertical and becomes loaded with the at least one liquid active composition from the top downwards, and the external surface of the substrate is exposed to the flushing water. 